Relative Humidity Plays Major Role in Comfort of Home

By Marantz, Ari | Winnipeg Free Press, November 14, 2015 | Go to article overview

Relative Humidity Plays Major Role in Comfort of Home


Marantz, Ari, Winnipeg Free Press


QUESTION: My 977-square-foot home, built in 1962, was retrofitted with a high efficiency furnace a couple of years ago. The usual story, we now have a humidity issue in the winter. The house never had a fresh-air duct and is tightly sealed, as tested by Manitoba Hydro. The hot-water tank was changed over to an electric unit. The chimney was capped and the flu pipe is no longer used. I am considering installing an energy recovery ventilator (ERV) to reduce the humidity. Or, perhaps a damper controlled fresh-air intake would be sufficient. Since we have an unused flu pipe running from the basement to the roof, can this be used for either an intake or exhaust for ventilation? What would you recommend?

Thanks and regards, Dave Laurie.

We have a problem with moisture leaking into our attic from a disconnected bathroom fan vent that has resulted in the development of frost. This discovery led to a discussion regarding the appropriate relative humidity inside our house. One source indicated once the outside temperature drops to 0 C, the indoor humidity should be at 40 per cent, but when it drops below -12 C, it should drop to 30 per cent, and even lower at -24 C, at 20 per cent. Other sources have told us that indoor relative humidity should stay between 30 to 50 per cent, otherwise structural issues such as cracking drywall and separating hardwood floors can arise, as well as health issues. We purchased a hygrometer and it is consistently reading between 34 and 39 per cent. Is there a definitive answer to the safe measure of indoor relative humidity?

Thanks for your time, Dianna and Al Sveinson.

Answer: While your two questions appear to be quite different on the surface, the underlying theme of moisture control is consistent. We will look at the reasons for moisture issues in the heating season and provide guidelines for minimizing this common problem.

Yes, it is that time of year again where the outside temperatures are beginning to creep below the magic freezing point of 0 C, especially at night. Because of this, our homes are now mostly sealed against the cold with the heating systems running regularly. When we start this yearly heating cycle, we are trapping warm air inside our comfortable abodes. Contained in this heated air is a certain amount of moisture, dissolved as invisible water vapour. If this level of moisture, typically referred to as relative humidity (RH), is allowed to rise too high, problems can occur. These problems can range from a small amount of condensation on our windows to major mould-growth issues on walls and ceilings. To combat this, we must try to find a balance between proper ventilation and personal comfort.

As you have experienced in the house in the first inquiry, high RH issues can often begin to occur when various energy efficiency upgrades are done.

This is because all of these upgrades tend to make the building envelope, or the interface between outside and inside, less permeable to air movement. Unfortunately, the former openings in these locations, such as the old furnace chimney, acted as natural ventilation to let out damp air while old windows and doors let in fresh, dry air. …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Note: primary sources have slightly different requirements for citation. Please see these guidelines for more information.

Cited article

Relative Humidity Plays Major Role in Comfort of Home
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen
Items saved from this article
  • Highlights & Notes
  • Citations
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Search by... Author
    Show... All Results Primary Sources Peer-reviewed

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.